Fist of the Imperium

"Let their noble sacrifice fill our world with power." Deep in the Segmentum Solar, on a world that they vowed to protect, the warriors of the honorable guard of the Imperial Fists are perishing. The culprit is a mysterious cult... that grows stronger by the day, ensnaring the inhabitants of the planet Gair - from impoverished miners to carefree aristocrats. To combat this threat, the Imperial Fists send the librarian-primaris Aster Lidorran and his diligent brothers. But the masters of siege warfare face a cunning enemy they have never encountered before. Dark omens abound, and Lidorran finds himself caught in a battle of mind and will against an opponent whose psychic power may surpass that of the librarian. And the enemy is patient - for with each hour, Gair draws closer to ruin. The steadfast sons of Dorn must leave their homeland and accept the aid of new allies to prevent a catastrophe at the very doorstep of Terra.